Amine flotation reagents

ABSTRACT

A new class of useful reagents for ore beneficiation are obtained by the reaction of N,N-dialkyl alkylene diamines and N, N-dialkyl-N&#39;&#39; -alkyl alkylene diamines with reconstituted tall oil. The reagents are particularly useful for the flotation separation of ore values from siliceous materials.

United States Patent 1 Grannen 1 June 18, 1974 AMINE FLOTATION REAGENTS 2,569,417 9/1951 Pay et al. 260/404.5 1751 Inventor: Edward Gram, Upland, Calif- 5532:??? 3113i? ii iil t'iIIIIIIII 31:111.??1Z72 73 Assignee; occidental petroleum corpomfion, 2,823,159 2/1958 Webb....- 167/38.7 LOS Angeles 3,280,140 10/1966 Sharkey 260/309.6 3,408,317 10/1968 Vertnik 260/18 [22] Filed; Nov. 6, 1972 3,558,500 1/1971 HOlllS 260/975 [21] Appl. No.: 304,007

Primary ExaminerMelvyn I. Marquis Related Application Data Attorney, Agent, or Firm-Christie, Parker & Hale [63] Continuation-impart 0f Ser. No. 467, Jan. 2, 1970,

abandoned.

52 us. c1 260/975, 44/66, 209/166, [57] ABSTRACT Int Cl 260/18 260/309'6 A new class of useful reagents for ore beneficiation 6 v are obtai e the ea ion of alky ene [581 Search 260/9735 3 13 diamines and N,N-dialkyl-N' -alkyl alkylene diamines 167/ 9/1 with reconstituted tall oil. The reagents are particularly useful for the flotation separation of ore values [56] References Cited from siliceous materials.

UNITED STATES PATENTS 2,494,132 1/1950 Jayne 209/166 6 Claims, N0 Drawings AMINE FLOTATION REAGENTS This is a continuation in part of my application Ser. No. 467 filed January 2, I970 now abandoned.

BACKGROUND OF THE INVENTION The present invention relates to a new family of amine flotation reagents in particular those based on the reaction product of reconstituted tall oil acid which are highly selective for the separation of ore values such as phosphate rock from siliceous materials.

Phosphate rock occurs widely in nature and contains as one valuable constituent impure calcium fluorphosphate. The deposits however, also contain siliceous materials, such as silica which are valueless constituents. Other valueless constituents such as calcium carbonate, some carbonaceous materials and heavy minerals may also be present.

Many methods have been used to beneficiate or concentrate the phosphatic constituents by flotation from the siliceous, carbonaceous and heavy mineral.constituents. Commonly, partial concentration is first employed to remove slimes and the phosphate values are then extracted using two beneficiation separations.

The first involves a crude flotation of phosphate values through the use of a fatty acid and caustic in combination with a petroleum fraction, such as kerosene. These reagents are mixed with the aqueous suspension of phosphate rock and the mixture is agitated and aerated. The phosphate values tend to concentrate in the upper portion of the cell for separation.

The enriched fraction, typically known as the rough concentrate, still contains 8 to percent siliceous matter which is attempted to be separated from the phosphate rock in a second flotation using a cationic reagent. The cationic reagents used have been long chain fatty acid amines or the salts, thereof.

One class of fatty acid amines used are those obtained by the reaction of fatty acids and ammonia in a two-stage reaction system. A nitrile is initially produced which is reduced to form the amines. The product usually contains a high concentration of free nitrile groups.

Another amine system, described in US. Pat. No. 2,927,692, has also been proposed. Thisreagent system is obtained by the condensation of fatty acid with an alkylene polyamine or a polyalkylene polyamine. The product is a monoor diamine which contains a number of free amine groups depending on the molar ratios of materials employed in the reaction.

While both amine systems are utile, their selectivity for siliceous materials is somewhat limited and the degree of separation of the phosphate rock from siliceous materials has been less than that desired.

SUMMARY OF THE INVENTION It has now been found that monofunctional N,N- dialkyl alkylene diamines and N,N-dialkyl-Nf-alkyl alkylene diamines will react with saturated, unsaturated and hydroxy fatty, acids particularly reconstituted tall oils by a condensation reaction to yield amines having free tertiary amine groups. These amines and the salts thereof have been found to be selective beneficiation reagents for the separation of mineral values, such as phosphate rock, from siliceous materials.

The preferred reconstituted tail oil acid-amines are obtained by reacting from about 0.9 to about 3.7 molar equivalents of reconstituted tall oil per active amine 2 group in an amine system containing at least one N, N- dialkyI-alkylene diamine or a N,N-dialkyl-N'-alkyl alkylene diamine or a mixture thereof, at a temperature of from about l30C to about 260C for a time sufficient for the condensation reaction to occur.

The reconstituted tall oil amine reaction product formed and their salts are unusually selective reagents for the beneficiating separation of ore values, such as phosphate rock, from siliceous materials.

DESCRIPTION According to the present invention, there is provided a new class of fatty acid amines which are highly selective beneficiation reagents for the removal of siliceous materials from mineral ores.

The amine reagents of this invention are prepared, in general, by reaction of saturated, unsaturated and hydroxylated fatty acids or mixtures thereof and in particular reconstituted tall oil with at least one monofunctional diamine having the general formula:

wherein R is hydrogen or an alkyl group and R R" and R' are independently alkyl groups. The alkyl groups present may be straight chained or branched and preferably contain from about one to about four carbon atoms.

Illustrative but no wise limiting of the monofunctional N,N-dialkyl alkylene diamines and N,N-dialkyl- N'-alkylenediamines which may be used in accordance with the practice of this invention there may be mentioned N,N-diethylethylene diamine; N,N-diethyl-N- methylethylene diamine; N,N-dimethyl-l,2-propane diamine; N,N-diethyl-l ,3-propane diamine; N,N- dimethyl-l,3-propane-diamine; N,N-dimethyethylene diamine and the like.

In addition to at least one monofunctional N,N- dialkyl alkylene diamine or N,N-dialkyI-N'-alkyl alkylene diamine, there may be present in the reaction system, reactive polyfunctional amines such as alkylene diamines, polyalkylene diamines, polyalkylene polyamines and the like. The amounts which may be present, generally, range from about 0.6 to about l.5 mol per mol of monofunctional diamine.

The fatty acids which are reacted with an amine system containing N,N-dialkyl alkylene diamines and N,N-dialkyl-N-alkyl alkylene diamines to provide the most functional reagents of this invention are the reconstituted tall oils.

By reconstituted tall oil there is meant, in general, a reaction product containing on the average at most about 14 percent rosin acids, from about 72.0 to about 77.0 percent fatty acids and a minimum acid number of at least about 125. The preferred reconstituted tall oils contain by analysis from about 73 to about 76 percent fatty acids, from about I l to about 16 rosin acids, from about 10 to about 13 percent unsaponafiables and having an acid number ranging from about ISO to about 165.

As will be shown, the reconstituted tall oil-amine reaction products of this invention are far superior to disk amine reaction products with respect to their ability to separate acid insolubles (SiO from P The amount of acid employed for the condensation reaction is an amount sufficient to provide from about acids such as formic acid, acetic acid, propionic and hydrochloric acid, hydrofluoric acid and the like, to provide salts in which the novel fatty acid amines of this invention serve at a cation and where the anion is pro- 0.9 to about 3.7, preferably from about 1.0 to about 2.0 5 vided by the acid. These salts are also active reagents molar equivalent of reconstituted tall oil acid for each for the beneflciation of ores and most particularly seprimary or secondary amine available in the reaction lective reagents for the flotation separation of ore valsystem. ues from siliceous materials.

Accordingly, each of the N,N-dialkyl alkyl diamines Although they may be used alone in the beneficiation and N,N-dialkyl-N-alkyl alkylene diamines provided in of mineral values, the activity of the amine reagents of the reaction system in accordance with the practice of this invention may be further promoted by the presence this invention provide one functional group for reacof certain acid like petroleum derivatives such as kerotion with each molar equivalent of the reconstituted tall sene and the like in the system where flotation is caroil. Where polyfunctional amines, such as those set ried out. They may also be used in conjunction with forth above, arepresent, a fatty acid equivalent, within other beneflciating reagents for the separation of valthe range prescribed above, should be provided for ues from ores and the like. each amine group in the system'having an active hydro- The amount of the amines of this invention employed gen, namely the primary and secondary amines. in the beneficiation of ores is not narrowly critical.

Novel reagents provided in accordance with the Generally. amounts from about to about practice of this invention are typically obtained by conore pounds per ton of ore beneficlated may be used. densing the mixture of the fatty acid and amines at a temperature from about 130 to about 260C for a pe- While no wise limiting, the following are examples of riod of time sufficient for the system to complete the P P FP of the {love} ammes of {ms reaction Generally, d di on h mixture lnventlon as well as their use as flotation reagents for densation time from about 2 to about 6 hours or more the beneficlatlon 0f Oreswill be required.

The properties of the condensation product obtained EXAMPLES 1 To 15 will vary somewhat depending upon the provided mol A series of fatty acid-amine condensation reactions ratio of acid to amine. At lower mol ratios at condensacarried out using a reactor equipped with a stirrer, a tion product will readily dissolve in water. At higher condenser and a temperature indicator. in each inacid ratios, however, the product behaves generally stance, the amine and acid were added in specified more like the fatty acid used and shows a tendency to amounts to the reactor and the mixture heated with agidisperse rather than dissolve in solution. tation. An initial temperature increase was generally The tertiary amine groups are present in the amine observed when the amine and the fatty acid were condensation products of this invention in combination mixed. With additional heating, water began to distill with combined reconstituted tall oil acid and have been off at a temperature from between 140C and l50C observed to provide reaction products with highly seand continued to evolve until the temperature of the lective activity for separating of ore values, such as reaction mass reached about 220C to 230C. Reaction phosphate rock, from siliceous materials by froth flotatimes varied from about 3 to about 6 hours. The nature tion. of the amine fatty acids systems reacted and the mol ra- The tertiary amine groups also provide a functionaltios employed and general properties of the reaction ity which allows the formation of salts by reaction with mass obtained are shown in Table l.

7 Tab'E l Mole Ratio Example Fatty Acid Source Wt.% Amine Wt.% Acid/Amine Remarks 1. Tall Oil 84 N,N-dimethyl-l.3-propane diamine 16 [.82 Opaque solution two layers in standing 2. Tall Oil 78 do. 22 1.20 Clear Browrl Solution 3. Tall Oil 91.5 do. 8.5 3.68 4. Tall Oil 88 do. 12 2.50 Soluble at 40% 5. Tall Oil 86.6 do. l3.4 2.25 Solids Separation on Standing 6. Tall Oil 82.8 do. l7.2 1.54 Opaque Solution no phase separation 7. Oleic Acid 84 do. 16 L9 Clear, light yellow solution 8. Tall Oil Heads 84 do. 16 L83 Opaque Solution 9. Tall Oil Heads 77.8 do. l2.2 l.2l Insoluble l0. Tall Oil Heads 91.4 do. 8.6 3.64 Opaque Brown Solution ll. Distilled Tall oil 84 do. 16 1.83 12. Tall Oil 77.7 N.N-dimethyl-l.3-propane diamine ll.l l.2l

Diethylene Triamine H2 13. Tall Oil 84.5 N.N Dimcthyl-l.3-pr0panc diamine 6.2 L92 Diethylene Triaminc 9.3 l4. Tall Oil 84.7 N,N-Dimethyl-l 3-propane diamine 9.7

Diethylene Triamine 6.2 .92 15. Tall Oil Heads 34.5 N.N-Dimethyl-l.3-propane diamine 6.2 .92

Diethylene Triamine 9.3

l. Union Camp Corporation (XL .1 reconstituted tall oil acid containing from 72-77'7: by weight fatty acids. up to 14% by weight msin acids and having an acid number of at least I25. 2. Arizona Chemical Company. Acintol H-2I22 3. Arizona Chemical Company, Acintol D-Z9LR 5 EXAMPLE 16 To establish the utility of a reconstituted tall oilamine reaction product to separate silica (SiO by froth flotation there was employed a Unitol CX-l having the following analysis:

Rosin Acids 16.37r

the float or tails and concentrate (P were filtered,

F A 3 7 dried and weighed. Both fractions were analyzed for atty cl 5 .'I z unsaponifiables 16% P O and acid insolubles (S10 The results are shown Acid No. 164 10 m Table 11.

" Table 11 P. as P.,0.. w,r.% Acid Insol. .(Si0,)Wt.7z

Conc. Tail Conc. Tail Reagent Acid Reconstituted Tall Oil 31.51 1.57 2.59 93.96

Distilled Tall oil 32.24 1.39 4.2 93.7

Tall oil Heads 32.18 1.34 6.44 94.25

Oleic Acid 33.2 1.66 4.l0 94.96

The series of tests involved evaluation of the properties of the reaction product of a reconstituted tall oil known as UNITOL CS-l with N,N-dimethyl-1,3- propane diamine as compared to the reaction product of the same amine with distilled tall oil, tall oil heads and oleic acid for their relative performance to separation by froth flotation of silica from P 0 extracted from phosphate rock. The distilled tall oil and tall oil head were supplied by Arizona Chemical Company, the distilled tall oil having the product designation D296R and the tall oils heads having the product designation 2122. The oleic acid employed was a technical grade oleic acid supplied by Mathesorl, Coleman and Bell.

REAGENT PREPARATION PROCEDURE To prepare the reaction product for use in flotation tests there was in each instance added to a stirredreaction vessel first 105 grams of the selected fatty acid and then grams of the N,N-dimethyl-1,3-propane diamine. On mixing, there was an initial temperature increase of about 30C. A condensation reaction was carried out over a period of about 6 hours during which time very little material distilled over as a condensate although the reaction temperatures reached were in excess of 200C. The resultant end product was, in each instance, fluid on cooling to room temperature. The amine-acid reaction product was in each instance converted to its acetate salt for use as a flotation reagent.

REAGENT EVALUATION To evaluate the prepared flotation reagents there was employed a standard Minerals Separation Gell. The objection was to determine the amount of Phosphorus (P) reported as P 0 which could be extracted from phosphate rock as a function of the acid insolubles (SiO remaining in the P 0 In each experiment there was employed a phosphate rock containing about percent entrained free water. The rock was added to the cell with water to form a slurry of 20 percent solids density. A pH of the system in each instance was about 7.4. In each instance there was added with agitation the Table III shows that using the reconstituted tall oil-N,N-dimethyl-1,3-propane diamine reaction product as the base the relative percent increase in the amount of acid insolubles (SiO remaining with the The amine reagent prepared in Example 2 was used as a beneficiation reagent for the cleaner float of a Florida phosphate rock containing 10 percent insolubles in a concentration of 0.3 lb. per ton of phosphate rock. Kerosene was present as a frother. The results of the froth flotation separation are shown in Table IV:

Table IV Insol. Wt.% Bone Phosphate of Lime Assay,

Assay( %P,O Distr.(%) 7:

Concentrate 8.4.5.. 72.8 97.6 4.3 Tails .5 9.7 Head (Total) 100.0 63.0 100.0

EXAMPLE [8 The procedure of Example 17 was repeated except the amine was used at a concentration of 0.45 lb. per ton of ore process. The results are shown in Table V.

Table V L lnsol. Wt.% Assay(%P,O;) Distr.(%) Assayl Concentrate 8L1 73.7 97.3 4.0 Tails 15.9 9.0 2.3 Heads 100.0 63.1 99.6

EXAMPLE 19 The amine reagent prepared in Example 9 was used in place of amine prepared in Example 2. Florida phosphate rock was treated using amine in the concentration of 0.45 lb. per ton of phosphate rock with kerosene as a frother. Results of this beneficiation separation are shown in Table V1:

" Table V1 10 EPL lnsol. Wt.% Assay Distr. Assay Conc n r 4.7... 1.3- 97.6 3.7 Tails 15.3 10.0 2.4 Heads 100.0 64.1 100.0

EXAMPLE 20 The amine prepared in Example 1 was used to treat a rougher phosphate rock containing about 10 percent insolubles in a concentration of 0.5 lb. per ton. The results are shown in Table V11:

Table V11 BPL, Wt. lnsol. Wtflr Yield, BPL

Concentrate 69.2 2.6 98% 3Q Tails 3.5 93.96

EXAMPLE 21 22 The amine prepared in Example 2 was used for the beneficiation of phosphate at a high slurry density (22% 23%) and compared to a commercial amine (Control A) which was a reaction product of a tall oil acid and diethylene triamine. As shown in Table V111, below, on a relative, comparative basis, phosphate loss in the tails was lower and insoluble retention by the float was also low.

The performance of the amine of Example 2 was compared to the performance of an amine obtained by the condensation of tall oil acid with diethylene triamine at an acid to amine group ratio of approximately 1. The results are shown in Table 1X wherein the amount of siliceous insolubles in the concentrate was reduced by 50 percent:

What is claimed is:

l. The reaction product obtained by condensing a monofunctional diamine selected from the group consisting of N,N-dialkyl alkylene diamines and N,N- dialkyl-N'-alkyl alkylene diamines wherein each alkyl and alkylene group of said monofunction diamine contains from 1 to about 4 carbon atoms, with about 0.9 to about 3.7 mols of a reconstituted tall oil per mole of said monofunctional diamine at a condensation temperature of from about C to about 260C for a period of time from about 2 to about 6 hours, said reconstituted tall oil containing from about 72 to about 77 percent fatty acids, from about 1 1 to about 16 percent rosin acids, from about 10 to about 13 percent unsaponifiables and having an acid number ranging from about to about 165.

2. The salt obtained by contacting the reaction product obtained by condensing a monofunctional diamine selected from the group'consisting of N,N-dialkyl alkylene diamines and N,N-dia1kyl-N'-a1kyl alkylene diamines wherein each alkyl and alkylene group of said monofunction amine contains from about one to about four carbon atoms, with about 0.9 to about 3.7 mols of reconstituted tall oil, containing from about 72 to about 77 percent fatty acids, from about 1 1 to about 16 percent rosin acids, from about 10 to about 13 percent unsaponifiables and having an acid number ranging from about 150 to about 165, per mole of monofunctional diamine at a condensation temperature of from about 2 to 6 hours, with an acid selected from the group consisting of formic acid, acetic acid, proprionic acid, hydrochloric acid and hydrofluoric acid.

3. The reaction product as claimed in claim 1 in which the monofunctional amine is N,N-dimethyl-1,3 propane diamine.

4. The salt obtained in claim 2 in which the monofunctional amine is N,N'-dimethyl-1,3 propane diamine.

tem.

. v UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3.8l7,972' D t June 18, 1974 Inventor(s) u 4 Q n n It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 61, after "16" insert therefor Z Colomn 8, Table IX reads as:

Table Di Example 22 Control B Kerosene, lbsJton 1.2 1.2

Fraction, P 0

Concentrate 32.65 31.58

Tails 2.27 I 1.92

Acid Insol. Wt. 70

Concentrate 3.54 6.70

Tails 7 91.04 92. 99

Table IX should read as follows:

Page $222 8? UNITED STATES PATENT DFFICE I I CERTIFICATE OF CORRECTION Patent No. 1 1811979 Dated June 18 197L Inventor(s) w r A. Grannen It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

r- 1 Table IX L Example 22 Control B Amine 1bs./ton I 1.0 v 0.71

Kerosene, 1bs./ton 1.2 1.;2

Fraction, P 0 I Y Concentrate 32.65 31.58

Tails v I 2.27 1.92 Acid Insol. Wt. Z

Concentrate 3.54 I 6.70

Tails 91.04 92. 99

Signed and sealed this 29th day of October 1974.

(SEAL) Attest: MCCOY'M. GIBSON JR. 0 MARSHALL'DANN Attesting Officer Commissioner of Patents 

2. The salt obtained by contacting the reaction product obtained by condensing a monofunctional diamine selected from the group consisting of N,N-dialkyl alkylene diamines and N,N-dialkyl-N''-alkyl alkylene diamines wherein each alkyl and alkylene group of said monofunction amine contains from about one to about four carbon atoms, with about 0.9 to about 3.7 mols of reconstituted tall oil, containing from about 72 to about 77 percent fatty acids, from about 11 to about 16 percent rosin acids, from about 10 to about 13 percent unsaponifiables and having an acid number ranging from about 150 to about 165, per mole of monofunctional diamine at a condensation temperature of from about 2 to 6 hours, with an acid selected from the group consisting of formic acid, acetic acid, proprionic acid, hydrochloric acid and hydrofluoric acid.
 3. The reaction product as claimed in claim 1 in which the monofunctional amine is N,N-dimethyl-1,3 propane diamine.
 4. The salt obtained in claim 2 in which the monofunctional amine is N,N-dimethyl-1,3 propane diamine.
 5. The reaction product as claimed in claim 1 in which the reconStituted tall oil is present in an amount from about 1.0 to about 2.0 mols per mol of primary and secondary amine groups in the reactive amine system.
 6. The reaction product as claimed in claim 2 in which the reconstituted tall oil is present in an amount from about 1.0 to about 2.0 mols per mol of primary and secondary amine groups in the reactive amine system. 